phyllite

[ fil-ahyt ]

noun

1. a slaty rock, the cleavage planes of which have a luster imparted by minute scales of mica.

phyllite

/ fɪˈlɪtɪk; ˈfɪlaɪt /

noun

1. a compact lustrous metamorphic rock, rich in mica, derived from a shale or other clay-rich rock

phyllite

/ fĭl′īt′ /

1. A green, gray, or red metamorphic rock, similar to slate but often having a wavy surface and a distinctive luster imparted by the presence of mica.

Derived Forms

• phyllitic, adjective

Other Words From

• phyl·lit·ic [fi-, lit, -ik], adjective

Word History and Origins

Origin of phyllite¹

First recorded in 1820–30; phyll- + -ite ¹

Word History and Origins

Origin of phyllite¹

C19: from phyll ( o ) - + -ite ¹

Example Sentences

Two years ago, I scrambled into a six-foot-deep soil pit dug into this hillside to examine the crumbling phyllite rock just below the topsoil.

From Washington Post

Crouching in the dirt, I could see grass roots reaching deep into the soil, and crumbling rock called phyllite that spoke of centuries of evolution and decay.

From Washington Post

The soil is phyllite, or decomposing slate, the rock easy to crumble by hand.

From Washington Post

“Heat and pressure squeezed these layers and recrystallized them into schist” — after intermediate periods as shale, slate and phyllite.

From New York Times

It takes your basic quiet marine shales, which had been resting peacefully in nice horizontal layers on the sea bed, and squeezes and cooks them into phyllite. 

From Scientific American